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Dead-end zones of water distribution network pose special challenges for chlorine distribution modeling: Long residence times and varying flow rates can lead to significantly reduced chlorine levels or varying concentration profiles. Currently, no chlorine transport model is able to address these problems correctly. In this work, a generalized unsteady state chlorine transport model was developed, accounting for transport by diffusion and convection and for chlorine reaction in the bulk water or at the wall. The resulting partial differential equation was solved numerically using an Alternating Difference Implicit(ADI) scheme. Furthermore, experiments were conducted at a pilot scale dead-end distribution system. The results were analyzed to detail the bulk reaction mechanism and to obtain model parameters. Additionally, example model calculations of theoretical and experimental unsteady flow profiles are shown and analyzed. The model was found to generally represent the behavior in dead-end zones of water distribution networks very well. The quality of the model results was found to be influenced by the confidence in the model parameters.